
Large triangular domains form where the two layers are in quasi-registry of alternating AB and BA type, minimizing the local interlayer stacking fault energy, with the dominant deformation inside the domains being a local counter-twist of each layer.

These domains are separated by narrow domain walls of shear type, meaning that the interlayer translation (Burgers vector) across the boundary is parallel to the domain wall itself, with three possible orientations, experimentally distinguishable (see Figure REF ).

The domain walls intersect at nodes of AA type (see e.g. Figure REF ), which due to their nature as maxima of the GSFE are pinned and act as topological defects [1]}, [2]}, and where an additional twist can be observed, dramatically reducing the area of the node.

